John Ayrton Paris, an English physician, born in Cambridge, Ang. 7, 1785, died in London, Dec. 24, 1856. He graduated M. D. at Oaius college, Cambridge, in 1808, and in the same year engaged in the practice of his profession in London. Soon afterward he settled in Penzance, Cornwall, and while there founded the royal geological society of Cornwall. In 1817 he returned to London, and delivered lectures on the materia medica and the philosophy of medicine, the matter of which was reproduced in his " Pharmacologia " (8vo, 1819; 9th ed., rewritten, 1843). In 1844 he became president of the London college of physicians, which post he retained until his death. He published a memoir of Sir Humphry Davy (4to, 1810); a " Treatise on Diet" (8vo, 1826); " Philosophy in Sport made Science in Earnest;" and in conjunction with J. S. M. Fonblanque, " Medical Jurisprudence " (3 vols. 8vo, 1823). He invented the "tamping bar," an iron implement coated with copper, which protected miners from the sparks evoked by the ordinary iron bar.